Epitaxial substrate for solid-state imaging device with gettering sink, semiconductor device, back illuminated solid-state imaging device and manufacturing method thereof

A method of manufacturing a silicon wafer, comprising:

• a slicing step of slicing a silicon single crystal ingot to obtain a silicon wafer;
• a multi-photon absorbing step of forming a gettering sink in which a crystal structure of an arbitrary microscopic region is changed, by causing a laser beam to be incident on one surface of the silicon wafer through a condensing lens and condensing the laser beam in the microscopic region, to cause a multi-photon absorption process to occur in the microscopic region in the silicon wafer;
• a polishing step of mirror-polishing the one surface of the silicon wafer after the multi-photon absorbing step so as to remove minute flaws on the one surface of the silicon wafer, and
• an epitaxial growing step of growing an epitaxial layer made of a silicon single crystal on the one surface of the silicon wafer after the polishing step;
• wherein the laser beam is an ultra-short pulsed-laser beam having a pulse width in a range of 1.0×10−15 to 1.0×10−8 seconds, a wavelength in a range of 300 to 1,200 nm, and
• an output power per pulse in a range of 1 to 1000 mJ, and the condensing lens condenses the laser beam to an arbitrary position in the thickness direction of the silicon wafer,
• wherein in the multi-photon absorbing step, a temperature of a condensing point of the laser beam reaches 9,900 to 10,000 K;
• and
• wherein in the multi-photon absorbing step, a portion of silicon atoms on the one surface of the silicon wafer is evaporated by the laser beam and the minute flaws occur in the one surface of the silicon wafer, while the silicon wafer is irradiated with the laser beam.